Improved process of roasting- and chlortdizing ore



HENRY TINDALL, OF

CHICAGO, ILLINOIS.-

Lctters'Patcnt No. 83,121, dated October- 13, 1868.

IMPROVED PROCESS OI ROASTING-YAND CHLORIDIZING- ORE.

The Schedule referred to in these Letters Patent and making part of the same.

To all whom it mil/y concern:

Be it known that 1, Emmy TIINDALL, of Chicago, Cookcounty, State of Illinois, have discovered a new and improved Process for Desulphurizing and Ghlorinating or Ohloridizing Ores. v

This invention relates to a process of desulphurizing and chlorinating orescontaining precious metals, and

' it consists in treating such ores during the operation of roasting, and desulphurizing them with dry chlorine gas, as will be more-fully described hereafter.

To enable others skilled in the art to practise my invention, I will proceed to describe one method of putting the same in practice.

I employ any of the furnaces in commonuse, or a furnace of any suitable construction, for desulphurizing ores, in which heat is employed as the agent for such desulphurization, and which contains a closed chamber in which the ore is to be treated.

In some convenient position, and adjacent to such furnace, I erect a small furnace, which is divided into an upper and lower compartment by a plate of metal, or of soapstone, or any material capable of resisting the action of the heat caused by the burning fuel in the lower compartment. Upon this dividing-plate, I place a cup-shaped vessel, of sufficient-dimensions to contain the gas-generating vessel, and leave sufficient space around it for a body of water to act as the medium for carrying the heat to. the gas-generating vessel. Into this open-ended vessel, I place a closed vessel containing muriatic acid,'an d manganese, or any other substances capable of giving ofi considerable quantities of chlorine gas in a dry state or condition.

To the upper portion of such vessel I attach a pipe, which communicates directly with the chamber in which the ore is being treated, so that, as a fire is kindled in the lower portionof the furnace, its heat is imparted to the division-plate, which, in its turn, heats the water forming the-bathin which the generator sits, and causes gas to be generated, which passes directly to the desulphurizing-chamber, filling such chamber, or such portions of it as are where the ore is, and, at the same time, filling the interstices between the pieces or particles of such ore with a medium much more dense or heavier than the gaseous products of combustion, or the vapors which arise from the ore during its treatment. I

' While gas is being admitted to the desulphurizing and 'chlorinating-chamber, the fire is kept up under said chamber, and in cases where the products of combustion are allowed to come in contact with the ore in escaping from the furnace, they, with the'fumes and vapors which arise fiom the ores, are compelled to rise or pass through this dense medium, which, it

is believed, has the effect of arresting avery large proportion of the particles of metal held in suspens'ion by such gases and vapor, and which,-.in all previous processes with which I am acquainted, causes great loss to the'opera'tor.

My process is designed to-prevent the above-indicated loss of the precious metal, and it is regarded as well calculated to accomplish that end, as it is contended that the density of the gas employed is suificient to arrest those minute particles which usually escape,

and retain them in the chamber until the ore is in the- The process of treating ores, substantially such as is above described.

' HENRY TmDALL.

Witnesses:

ALBT. B. Wm'm, W. H. Nonnns. 

